Cylindrical drum-shaped canteens having fabric end panels have been manufactured for many years. The end panels of the canteen are fabric covered to provide an evaporative surface for cooling the canteen or merely an insulative cover. The core of the canteen is a cylindrical plastic watertight container with a capped opening extending through the periphery of the tank. The relatively thin plastic tank is surrounded by a sheet metal frame which provides the basic rigidity to the tank along with a means for holding the overall structure together and carrying the supporting straps. The longitudinal edges of the metal frame are bent inwardly into contact with the circumferential edges of the tank and the cloth end panels covering the ends of the tank.
The sheet metal frame rolled from a planar strip is held together at its ends by a lap joint. The prior art method of forming this lateral joint, in all instances, exposes a sharp edge of the sheet metal which is usually not deburred and quite often creates a hazard for not only the people using the canteen but also the problem of abrading whatever it contacts. The prior art method of providing support loops in the frame for the carrying straps is done by first cutting two parallel slits and then deforming the area therebetween upwardly to create a pair of widened slots. This particular design is very abrasive upon support straps due to the sharp ends of the slits coming into a scissor contact with the fabric support straps which pass therebetween. The present invention utilizes, in place of the slits, a stamped slot having a rounded end so that the support strap cannot be abraded. Also, the frame member of the present invention has an overlapping lateral joint shaped so that when in place, there are no sharp edges along the joint to catch or abrade.
It is therefore the principal object of the present invention to provide an improved sheet metal frame on a conventional cylindrical canteen structure.
Another object of the present invention is to provide an improved canteen design which does not have to be individually deburred.
Another object of the invention is to provide an improved support strap loop formed in a sheet metal frame.